In the past, computer users have relied upon network file servers to provide distributed file services between the file server and a separate storage system. Files would be transferred from host computers over a network to the file server. The file server would then use any of several methods for storing the files on remote disk drives, usually via an I/O channel connection. Expensive servers such as Microsoft NT servers or Sun Solaris servers have been employed in front of expensive storage systems to provide this functionality. This has been found to be a relatively cumbersome and expensive solution.
Designers and manufacturers of storage systems have developed technology integrate these systems. The newer storage technology is known as a network accessed storage system, or NAS. A NAS is a storage system that connects directly to a network, such as a Gigabit Ethernet network. The NAS contains an integrated file server or controller for delivering distributed file services to hosts. File I/O is transferred over the network connection, and is cached in the NAS system and stored on the disk drives, and vice-versa.
Current NAS systems typically employ many different chassis holding equipment that performs various specific functions, making the NAS quite inflexible. Furthermore, the use of optical connectors and cables is often required to connect the various chassis. Though less expensive than remote server solutions, significant cost is incurred in providing a NAS because of these issues. There are now many storage customers that desire NAS functionality but want or need a lower cost system. A more flexible NAS system that can be manufactured and maintained at significantly lower costs than current systems is therefore highly desirable.